Cefixime (DB00671): A Comprehensive Pharmacological and Clinical Monograph

1.0 Executive Summary

1.1 Overview of Cefixime

Cefixime is a semisynthetic, orally active, third-generation cephalosporin antibiotic. Identified by DrugBank Accession Number DB00671 and CAS Number 79350-37-1, it is classified as a small molecule drug.[1] Cefixime exerts a bactericidal effect by inhibiting the synthesis of the bacterial cell wall, a mechanism characteristic of β-lactam antibiotics.[1] Its chemical structure confers stability against many common β-lactamase enzymes, allowing it to maintain efficacy against pathogens that are resistant to penicillins and earlier-generation cephalosporins.[2]

1.2 Key Pharmacological Characteristics

The pharmacokinetic profile of cefixime is notable for its partial oral absorption (30-50%), which is significantly influenced by the pharmaceutical formulation; the oral suspension achieves higher peak concentrations than solid dosage forms.[5] Food delays the time to maximum concentration but does not substantially alter the overall absorption of tablets and suspension.[4] The drug is approximately 65-70% bound to plasma proteins and is distributed to various tissues, including the respiratory and urinary tracts.[5] Critically, cefixime is not metabolized in vivo and is primarily excreted unchanged by the kidneys, with a smaller fraction eliminated through the bile.[4] This reliance on renal clearance mandates dosage adjustments in patients with renal impairment. The elimination half-life averages 3 to 4 hours, which supports convenient once or twice-daily dosing regimens.[7]

1.3 Summary of Clinical Applications and Limitations